2. *BASICS*
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DNA is fundamental for all life - it contains genes (short sections of
DNA), which code for making different proteins, the building
blocks of life.
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DNA is what you find, tightly coiled up, inside all 46 chromosomes
in every nucleus in every single human diploid body cell.
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It consists of two strands coiled together with a double helix
structure and just 4 base pairs:
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A (adenine) <—> T (thymine)
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C (cytosine) <—> G (guanine)
3. *FRANKLIN & WILKINS*
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Franklin and Wilkins were the brains behind DNA and it’s structure:
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They emitted X-Rays at the crystallised DNA and recorded the
patterns of the reflected rays onto a screen.
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From this they discovered the DNA’s helical structure
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*WATSON & CRICK*
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Watson and Crick used information of the double helix
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and that the amount of A + G was equal to the amount of C + T to
make a model of DNA with the paired bases.
5. *STEP 1*
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Chop a big juicy fresh onion into tiny pieces.
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Put it into a beaker.
6. *STEP 2*
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Add salt and detergent to the onions and stir.
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The detergent will help to break down the cell membranes;
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The salt helps to make the DNA stick together.
7. *STEP 3*
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Put the beaker into a water bath.
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Set the water to 60 celsius for 15 minutes and then remove the
solution.
8. *STEP 4*
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Cool the solution with ice.
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This stops the DNA from breaking down.
9. *STEP 5*
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Blend the mixture.
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To open the cell walls and reelase the DNA.
10. *STEP 6*
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Cool the solution with ice.
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This stops the DNA from breaking down.
11. *STEP 6*
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Filter the mixture.
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Removing any big parts of cell and stop froth.
12. *STEP 6*
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Add ice cold alcohol to the solution.
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Do this slowly, and you should see the DNA separating from the cells
as a white stringy substance, which can be removed with a glass rod.